Anybody have an issue w/ traction control from two different size tires on an 02?

I have 225/40/18 tires on my car wich i swear are the hardest tires to find. I found one so i bladah bladah i guess a few more tires than i thought were messed up so they decided they would help me and put two different size ones on the back 235/45/18 i believe (cars been in the shop for the past 3 days so havent had the chance to look) i didnt think thatd be an issue since most cars can but VW are tricky. Well i leave and a light on my dash that ive never seen before pops up wich is for traction control i figured out. I wasnt able to do over 35 without my car feeling like it was shifting its self then itd speed up and id get to 45 and not accelerate over, when id brake itd feel like it was getting stuck half way and fighting me. I brought it back to shop where im twlling them it didnt happen till i left and they are trying to convince me its a bigger issue like my cam shaft sensor wich and just a coincidence, my car isnt in the best shape as i bought it used but i have never had an issue with it not driving right till i left that place. I figured out i could disable the asr and she drove fine for a little while besides rhe brake was atill acting up. The nxt day i drove to work and its wanting to accelerate when i was stopped felt like it was jumping, i had to pull the e brake a couple times to stop from hitting a car & then she stalled out. So i bought the cam shaft sensor and when i called to check on my car 3 days ago they told me they ran into elevtrical issues and need to run some wires like they really just dont know what thwyre doing. Im freaking out. Has anyone had this issue before from 2 different tires? Could it just be the traction control messing up from one set of the tires going faster than the other thinking that the car is skidding.